AAPT2: Insert platformBuild information

Inserts platformBuildVersionName and platformBuildVersionName when the
attributes are not currrently present. The attributes are set to
the values of versionName and versionCode.

Bug: 77541121
Test: Build apk using aapt and appt2 and dumped using xmltree to confirm
the presence of the attributes
Change-Id: I5330381905c878fb877214b42f83d7e2e48cd062